Future of fitness apps lies in understanding human movement

Can you log a weightlifting workout with the Workout app's "Other" option? Not really. Photo: Graham Bower/Cult of Mac

Some Apple Watch users are apparently confused over what types of exercise the wearable’s Workout app can track. Many people are using it to log weightlifting or stretching sessions, even though Apple only claims the app is suitable for “dedicated cardio workouts.”

Fortunately, a new breed of fitness apps is emerging that uses the accelerometer access enabled by the recently released watchOS 2 to track strength and flexibility workouts more effectively.

Stretching the limits of the Workout app

You can log a variety of cardio workouts, including running, cycling and rowing, by selecting them from the list of activities in the Apple Watch’s built-in Workout app.

There is also an “Other” option, which appears to be a catch-all for any other kind of exercise. But what, exactly, can you use it for?

The Workout app monitors your heart rate and the quantity of your movement to estimate the number of calories you are burning from exercise. It is designed specifically for cardio exercise, which is all about elevating your heart rate and burning calories. So the Other option is great for logging movement-based workouts like a Zumba class, but it is not ideal for non-cardio exercises, like strength and flexibility training.

The trouble is, this is exactly how many people are using the Other option, according to the results of a new survey by the analysts at Wristly. When they asked Apple Watch owners what they use the Other option for, two of the most popular responses were weightlifting and stretching — in other words, strength and flexibility training.

Strength training is about building muscle, not burning calories. To log this kind of workout, you need to know exactly what move you are performing, how many reps you are doing and the weight you are lifting.

Stretching, on the other hand, is intended to improve your flexibility. To log this, you need know what joint is moving and how the range of motion in that joint is increasing over time.

These are not things that the Workout app can tell you. But two companies, FocusMotion and VimoFit, launched solutions for Apple Watch this week that promise to effectively track these types of workouts.

FocusMotion — understanding human movement

Back in August, I speculated that Los Angeles-based startup FocusMotion might bring its automatic workout-tracking solution to Apple Watch. Sure enough, now they have, with the launch of their SDK for iOS developers. FocusMotion CEO Cavan Canavan spoke to me this week about his company’s plans for Apple Watch and its vision for “understanding human movement.”

Back in 2013, FocusMotion launched a fitness app for the Samsung Galaxy Gear called Focus Trainr. The company has shifted its strategy away from developing its own app, instead focusing on the underlying technology FocusMotion developed for automatic exercise recognition and rep counting.

Now FocusMotion licenses this special sauce to third-party developers, who can use it to build their own fitness apps. Canavan is hoping big brands will adopt his tech and use it to build a new generation of workout apps.

Apple Watch apps powered by FocusMotion will be able to automatically detect the exercise you are performing and count your reps using nothing more than the motion of your wrist. Currently the system can only recognize 24 exercises, though more are being added. It can count reps for more than 50 different exercises.

These waveforms show the unique motion patterns generated by your wrist when you perform different exercises. FocusMotion’s technology can recognize these patterns to identify an exercise.Photo: FocusMotion

One big advantage of FocusMotion’s approach is that apps can tell how consistently you are performing an exercise and measure your tempo — how fast you are raising and lowering the weight.

But there are also some disadvantages. Canavan acknowledges that the system is not yet perfect — its average accuracy is currently at 95%. Since you wear your watch on your wrist, the accelerometer can’t tell you anything about exercises where your wrist does not move (like leg curls, for example). Plus, wrist-based sensors can’t tell how heavy the weight is that you are holding in your hand.

Since most gym-goers would be reluctant to strap an Apple Watch around their ankle, there is not much that can be done about this. Similarly, since you only wear your watch on one wrist, FocusMotion can’t identify unilateral moves (where you move one arm at a time).

With these limitations in mind, Canavan argues that while FocusMotion’s solution may not yet be suitable for serious bodybuilders who perform advanced moves, it is ideal for mass-market users.

FocusMotion’s vision goes beyond fitness. The company is already exploring other applications for its technology, including physiotherapy and even a means for police forces to monitor when their officers are using firearms.

If you are a developer, you can download the FocusMotion SDK for Apple Watch today. The rest of us wanting to try it out will have to wait until the first third-party apps get released. And Canavan estimates this may not be until the beginning of next year.

VimoFit Tracker for Apple Watch is out now

If you want to try motion-based exercise logging right now, you’re in luck. VimoFit Tracker for Apple Watch was released this week, and it is currently a free download on the App Store. It is not based on FocusMotion. Instead, VimoFit uses its own high-tech wizardry to recognize your exercises and count your reps.

The Watch app is well-designed, with a clean, simple interface that makes it easy to log workouts. In my tests, I found the rep counting to be quite accurate, but I had to teach it most of the moves I was doing, a process that involved speaking the name of each exercise into the watch. In a noisy gym environment, this can produce some unexpected and funny results. Like when I tried to teach it “skull crushers” and it thought I said “school crushes.”

Like FocusMotion, VimoFit Tracker suffers from the same limitations of wrist-based sensors: You have to log weight manually, it does not recognize leg curls, and I struggled to log unilateral moves. When an exercise is not recognized automatically, you can still enter it manually.

With some manual entry, I was able to log a complete strength-training workout entirely from my wrist, without ever having to take my iPhone out of my pocket. Which is an impressive feat.

A glimpse of the future of fitness tech

FocusMotion and VimoFit Tracker are both impressive in their ambition. They have limitations, but they are sure to improve over time. Right now, motion recognition is at the early adopter stage, and it may not be ideal for everyone, but I think these apps give us a good idea of where fitness tech is heading.